(listp)
(listp 8)
(listp (quote bb))
(listp (quote (a b c)))
(listp ())
(atom)
(atom 8)
(atom (quote bb))
(atom (quote (a b c)))
(atom ())
(null ())
(null (quote bb))
(null (quote (a)))
(null 88)
(integerp 3)
(integerp (quote bb))
(integerp (quote (a)))
(integerp ())
(integerp (quote ()))

; should fail
((show))
((quote 8))
(())
